The team is comprised of dedicated aviation safety professionals with experience and expertise in rotorcraft, vertical lift, and eVTOL/urban air mobility.
Meet the team

Charles “Cliff” Johnson
Lead Research Engineer,
FAA
Cliff Johnson is a research engineer, program manager, and technical expert for the Aviation Research Division at the FAA William J. Hughes Technical Center in Atlantic City, NJ. He leads several research and development activities that seek to improve aviation safety, primarily focused on rotorcraft, unmanned aircraft, and vertical lift (i.e. eVTOL). He joined the FAA after earning a bachelor’s degree in mechanical engineering (B.S.M.E.) from Rowan University. He is an instrument rated commercial pilot who is also pursuing flight instructor, multiengine, and helicopter add-on ratings.

Lacey Thompson
Co-Research Lead and Operations Research Analyst,
FAA
Lacey Thompson is an operations research analyst, who currently serves as co-research lead of the rotorcraft/vertical flight safety team and Program Manager for Collision Risk Modeling which supports System Safety Management research within the Aviation Research Division (ARD). She has a B.S. in physics from Northwestern State University and a Master of Science in aeronautics from Embry-Riddle Aeronautical University. Before joining the ARD, Lacey was part of the Unmanned Aircraft System (UAS) Engineering Branch working primarily on the safe and efficient integration of UAS into the national airspace system.

Stephanie Stead
Computer Scientist, FAA
Stephanie holds a BS in computer science and information systems, graduating with Honors from Stockton University in 2019. She is currently working toward her master’s degree in aviation Cybersecurity with Embry-Riddle Aeronautical University. Stephanie performs a variety of tasks as a member of the Rotorcraft Research Safety Team. Specifically, serving as a cybersecurity analyst, programmer, and flight test engineer. In addition to these duties, she is also a member of the Cyber Security Data Science Team, working with industry partners to create a cybersecurity test environment for Industrial Control Systems.

Lyndsay Digneo
Engineer, FAA
Lyndsay Digneo is an engineer, who currently serves as the co-lead for the Vertical Flight Safety Aviation Technologies (VFAST) Lab and supports the rotorcraft/vertical flight safety team specifically in the area of immersive flight technologies within the Aviation Research Division (ARD). Prior to joining the ARD, Lyndsay managed several aviation weather laboratory environments, led research efforts for emerging aviation weather capabilities, and represented the FAA Technical Center on cross-agency working groups focused on future workforce development. She has a B.S. in Electrical and Computer Engineering from Rowan University and a M.S. in Electrical Engineering from Drexel University.

Julian Babel
Computer Engineer,
FAA

Timothy Kuhn
General Engineer,
FAA
Tim graduated with a B.S. in Electrical and Computer Engineering in 2019. He is with the Software and Systems Branch of the Aviation Research Division. He started with the FAA in their Gateways Internship Program and converted to full-time work with the team just last year. Currently, his focus is on developing cyber capabilities for the VFAST simulators and supporting their operation across a variety of research studies.

Eleni Sotiropoulos-Georgipoulos
Aerospace Engineer, PhD
Eleni graduated with her M.Sc in Aerospace from ISAE-Supaero (France) and from Georgia Tech in 2022. She recently completed her PhD with the Georgia Tech Aerospace Systems Design Laboratory, ASDL, focusing on the use of flight simulators for Vortex Ring State accident prevention. She works at the FAA Technical Center for the Vertical Flight Aviation Simulation Team, VFAST, experimenting with their six helicopter and eVTOL flight simulators.

Jean-Christophe “Geff” Geffard
Principal Engineer, BCI
Geff has been providing Aeronautics and Electronics Systems engineering expertise for 35+ years. He is currently a principal engineer with Basic Commerce & Industries, Inc. supporting FAA safety and data management programs for multiple groups including VFAST, CASSIE, RDOE, EIM, HPC and Separation Standards.

Paola Zanella
Aerospace Engineer, PhD
Rotorcraft Safety Project Lead at Concepts Beyond, Contractor for the Federal Aviation Administration.

Andres Geffard
Biomedical Engineer, Johns Hopkins University
Andres graduated from Rowan University with a B.S. in biomedical engineering and is now a part-time biomedical engineering graduate student and assistant at Johns Hopkins University. At VFAST, he maintains and enhances flight simulators, conducts data analysis, develops the website, and designs custom parts and materials using CAD and additive manufacturing technology.

Maggie Mayfield
Flight Test Engineer and Pilot, EIT
Aviation professional dedicated to advancing safety and innovation in aerospace. Holds a B.S. in Physics with a certificate in Computer Programming from Rowan University and a Master’s in Industrial Engineering from the University of Iowa’s Operator Performance Laboratory. Currently serves as a flight test engineer and pilot with the FAA’s Rotorcraft Safety Research Team. Commercial pilot with an instrument rating and a former F-16 avionics technician with prior military service. Active AvSTEM ambassador, committed to inspiring the next generation of aviators and engineers.

Tyler Travis
Associate Director of Safety Research,
Rowan University
Tyler earned a B.S. in Business Administration with a concentration in Management Information Systems from Drexel University in 2012. Over the past 13+ years, Tyler has specialized in flight test engineering and data analysis, contributing extensively to the FAA’s Rotorcraft Research Team in its mission to enhance rotorcraft safety and performance research.

Phil Greco
Senior Aerospace Consultant,
EIT
Supporting FAA CSF facility, FDM research pilot, special aviation projects: AOA, ASTi, Rotorcraft and fixed wing studies.

John Geyser
Senior Aerospace Consultant,
EIT
Performing duties as a Flight/Aircraft Operations team member flying, evaluating, and improving the FAA’s Sikorsky S76D, Airbus H125, King Air, and Airbus A320 Simulators at the FAA Cockpit Simulation Facility (CSF) at the William J. Hughes Technical Center.

Abby Gunnels
Biomedical Engineer, EIT
Abby graduated with a B.S. in biomedical engineering and a concentration in biomaterials from Clemson University in 2025. She first started working with the FAA through the Gateways Internship Program. During this time she supported the Center Operations Division as well as the Aviation Research Division. Currently, she is a rotorcraft safety research engineer with EIT, contributing to the FAA’s VFAST research efforts and laboratory operations.

Karen DiMeo
Program Analyst, ATAC
Karen is a full-time program analyst with ATAC, supporting rotorcraft safety research at the FAA’s VFAST Laboratory since 2023. She graduated from Embry-Riddle Aeronautical University with a B.S. in Homeland Security and minors in Terrorism Studies and Strategic Foreign Languages, and is currently a full-time graduate student at the same institution. In her role, she supports the planning and execution of aviation-focused research initiatives, graphics and content development, external outreach, and lab operations. Additionally, she provides research and operational support, contributing to ongoing projects focusing on visual dominance in DVE, measuring cognitive workload, and control loading.


Partners & Collaborators

FAA Cockpit Simulation Facility
The CSF Team operates a set of high-fidelity aircraft simulators for human-in-the-loop research studies. Their simulators combine in-house developed software and hardware along with actual aircraft avionics, which provides very high fidelity in the simulation and at the same allows us to customize our simulators based on a customer’s unique requirements. This gives the ability to assist clients in their simulation goals, scenario development, and data collection. The CSF has supported various projects such as workload assessments, new integrated avionics, and weather technology in the cockpit.
